Non-pyrotechnic signature for medium caliber projectile

ABSTRACT

A visible or invisible light-producing device in an inert target practice projectile creates visible and/or infrared light initiated by a deceleration sensitive triggering element when the projectile impacts a target. A visible signature is creating for recording the impact to provide training without the use of any pyrotechinc, or other hazardous materials being deposited on the impact area. The light producing device may be initiated by fuze electronics—prior to actual impact—to facilitate simulating an airburst projectile for training or testing purposes.

UNITED STATES GOVERNMENT INTEREST

The inventions described herein may be manufactured, used and licensed by or for the U.S. Government for U.S. Government purposes.

FIELD OF THE DISCLOSURE

This disclosure relates to weapons systems. More specifically, this disclosure relates to target practice projectiles used for training and testing purposes.

BACKGROUND OF THE DISCLOSURE

Untraced target practice projectiles do not provide visual feedback to the user when impacting the ground or the target, so it is difficult if not impossible to assess the accuracy of the target practice shot and thus the performance of military personnel firing the weapon. In addition, training devices need to be non-dud producing to ensure the safety of range crews and users.

Current target practice projectiles that provide a visual signature contain flash producing chemicals that burn upon impact or just output a small cloud of colored material. These target practice devices require the outer projectile to rupture so as to provide a visual signature of the impact. These target practice projectiles are range and target limited due to the kinetic energy input needed to initiate a reaction that burns or disperses the contents of the projectile

SUMMARY OF THE DISCLOSURE

An advance is made in the art according to the principles of the present disclosure directed to a light emitting projectile that includes an electronically triggered flash-producing device within the target practice projectile.

The projectile employs electronics that are completely contained within the projectile. Energy required to produce the flash can be generated and stored onboard the projectile before the shot or as a result of it. The only kinetic energy required from the projectile is that required to close an electrical switch. The projectile advantageously provides more realistic live fire training for high energy, high explosive projectiles. Electrical operation can provide better and safer live fire training and testing with next generation air bursting and other munitions.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a depiction of a target practice projectile in accordance with one embodiment of the disclosure;

FIG. 2 is a depiction of a target practice projectile in accordance with a second embodiment of the disclosure; and

FIG. 3 is a 3D depiction of the target practice projectile in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

The following merely illustrates the principles of the disclosure. It will thus be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the disclosure and are included within its spirit and scope.

Furthermore, all examples and conditional language recited herein are principally intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the disclosure and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions.

Moreover, all statements herein reciting principles, aspects, and embodiments of the disclosure, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently-known equivalents as well as equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure.

Thus, for example, it will be appreciated by those skilled in the art that the diagrams herein represent conceptual views of illustrative structures embodying the principles of the disclosure.

In accordance with one embodiment of the invention described here, a light device is placed in an inert projectile, which would generate visible and/or infrared light initiated by a deceleration of a sensitive triggering element when the projectile impacts a target. A visible signature would be created for recording the impact to provide training without the use of any pyrotechnic or other hazardous materials being deposited within or on the impact area. The light generating device could also be initiated by fuze electronics, prior to actual impact, to facilitate simulating an airburst projectile for training or testing purposes.

One detailed example of the invention involves a light emitting diode (LED) in the base of a projectile body which would be powered upon impact with the target by a piezo-electric crystal, or other equivalent force transducer responsive to the deceleration of the projectile, to emit a visible a flash of light when the projectile impacts the target.

An illustration of such a projectile is shown in FIG. 1. This FIG. 1 shows a target practice projectile 10, which illustratively may be an existing LW30mm M788 TP Cartridge comprising a steel slug with an aluminum windscreen. The M788 TP projectile was designed to be inert so that there would be no contamination of practice ranges with unexploded ordnance (UXO). As presently constituted, there is generally no impact signature for the M788 TP other than kicking up some dirt/debris upon impact.

It would be desirable then to have a target practice projectile like the M788 TP that has a clearly visible signature indicating impact with a target, without any pyrotechnic or other components that could become UXO or lead to contamination of the target range. In this regard, the projectile 10 of FIG. 1 comprises a cylindrical metal body 12 attached to a roundly tapered nose 14 at the front of the projectile 10 and to a circular base 16 at the rear of the projectile 10.

Shown mounted within the nose 14 of the projectile 10 is a piezoelectric crystal 18 designed to be stressed as a result of the deformation of the nose 14, produced when the projectile 10 is fired from a gun and impacts a target. Stress of the piezoelectric crystal 18 produces an electrical signal conveyed by a pair of wires 20 and 22 in the body 12 connecting the piezoelectric crystal 18 to an LED 24 mounted in the base 16 of the projectile 10. The LED 24 is mounted to/within/upon the projectile 10 so that a visible flash of light is seen by target range personnel who are evaluating the shot.

Another example of a projectile according to the disclosure is shown in FIG. 2 whereby the LED in the base of the projectile is powered by batteries 26 instead of a piezoelectric crystal 18, as in FIG. 1. The batteries 26 are connected in series with the LED and a force sensitive switch that closes and completes the circuit between the batteries and the LED when the projectile impacts a target after having been fired. The LED in this example is protected from the propellant gases by transparent lenses. As in the device in FIG. 1, a flash of light is produced which is used by target range personnel to evaluate the shot. A 3D depiction of the projectile of FIG. 2 is shown in FIG. 3.

As may be appreciated however, batteries may not be the best solution since they contain undesirable chemicals that could contaminate the target range. It is preferred that a non-polluting power source, such as a set-back or inertial generator or the previously described piezoelectric generator, be used. In addition, suitable light sources other than an LED may also be used to produce the flash of light indication impact with the target. More particularly, light emitting devices that emit in non-visible portions of the electromagnetic spectrum, i.e., IR, UV may be employed as well.

Those skilled in the art will recognize that set-back or inertial generators generally utilize the relative movement of a permanent magnet with respect to a coil to generate a voltage pulse. Such generators may generate the voltage pulse upon launch/shooting and/or acceleration/deceleration and/or impact.

At this point, while we have discussed and described the invention using some specific examples, those skilled in the art will recognize that our teachings are not so limited. For example, any of a variety of projectiles of suitable size(s) may employ the teachings of the present disclosure. Additionally, any of a variety of known light sources and/or electrical power generating devices that can be readily accommodated within the confines of the projectile are possible and are but a few examples of modified variants of those explicitly disclosed herein. Finally, alternative triggering devices other or in addition to the switch shown may be employed. More particularly, timers may be employed such that an airburst effect may be produced as an alternative to the impact. Still further, RF or other proximity sensing devices may be employed such that the projectile emits light when it impacts/resides within a particular target area thereby providing proximity feedback. Alternatively, the projectile may emit visible, IR, or other light and/or a Radio Frequency pulse or other signal which activates an RF or light sensitive training target or scoring device. Accordingly, the invention should be only limited by the scope of the claims attached hereto 

1. A target practice projectile consisting of: a cylindrical body having a nose at the front end thereof and a base at the rear end thereof, the body containing an electrically actuated device that produces a non-pyrotechnic flash in response to impact of the projectile upon said target.
 2. The projectile of claim 1, in which the electrically actuated device is a light emitting diode.
 3. The projectile of claim 1, further comprising: a piezoelectric element that deforms in response to impact of the projectile and produces an electrical signal that electrically actuates the non-pyrotechnic flash producing device.
 4. The projectile of claim 2, further comprising a battery in series with the light emitting diode and an electrical switch that closes upon impact of the projectile and electrically actuates the light emitting diode.
 5. (canceled)
 6. The projectile of claim 1, further comprising one or more lenses for directing the non-pyrotechnic flash. 7.-8. (canceled)
 9. The projectile of claim 1 wherein said non-pyrotechnic flash comprises visible, infrared or ultraviolet light.
 10. (canceled) 